Former British prime minister David Cameron, whose decision to hold a referendum on European Union membership resulted in a vote to leave, said on Monday he would resign as a Member of Parliament.
The decision triggered a by-election for his seat in Witney, Oxfordshire.
Cameron, who took over leadership of the Conservative Party in 2005, was prime minister from2010 until June this year when he quit as leader following Brexit.
At the time Cameron, who is 49 and has been an MP since 2001, said he intended to remain on the House of Commons backbenches until the next general election, due in 2020, but instead said on Monday that he would quit.
"I've thought about this long and hard over the summer and I've decided the right thing to do is to stand down as the Member of Parliament for Witney," he told the BBC.
Cameron was widely blamed by many voters for holding the EU referendum, which was seen as an attempt by him to blunt the efforts of the anti-Europe group of Conservative MPs.
When this failed, he promised he would "do everything I can to make this great country succeed", but little had been heard from him since he quit as prime minister.
He told Independent Television News on Monday that he did not want to become a distraction for his successor, Theresa May.
Reuters contributed to this story.